/Engine/Source/Editor/GraphEditor/Public/SGraphNode.h
Check whether drag and drop functionality is permitted on the given node
static bool CanAllowInteractionUsingDragDropOp ( const [UEdGraphNode](API\Runtime\Engine\EdGraph\UEdGraphNode) * GraphNodePtr, const [TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [FActorDragDropOp](API\Editor\UnrealEd\DragAndDrop\FActorDragDropOp) > & DragDropOp )